Valve mechanism



(No Model.) 2 sheets-sheet 1.

D. COOPER.

VALVE MEGHANISM.

UNITED STATES',

PATENT OFFICE.

DYER COOPER, OF PHILADELPHIA, PENNSYLVANIA.

VALVE MECHANISNI.

SPECIFICATION forming part of Letters Patent No. 553,776, dated January28, 1896. Application led January 3, 1894. Serial No. 495,497. (Nomodel.)

To all whom, t may concern.-

Be it known that I, DYERVOOOPER, a citizen of the United States,residing in Philadelphia, Pennsylvania, have invented certainVImprovements in Valve Mechanism, of which the following is aspecication.

The object of my invention is to simplify the construction ofvalve-operating mechanism of steam-pumps, &c., by making the piston openand close exhaust-ports, allowing steam to exhaust from either side ofthe valvepiston, as fully described hereinafter.

A further object of my invention is to cushion the piston when usedespecially in a vertical pump or drill.

In the accompanying drawings, Figure l is a longitudinal sectional viewof suflicient of a pump illustrating my invention. Fig. 2 is atransverse section on the line 2 2, Fig. l; and Fig. 3 is a transversesection on the line 3 3, Fig. l.

I have shown in the drawings the pump arranged in a vertical position,but it will be understood that it can be arranged in a horizontalposition Without departing from my invention.

A is the cylinder having heads A A2, and in the cylinder-casting areports a a', through which the steam ,enters'and escapes.

a2 is the exhaust-passage, which is open to either port as dictated bythe slide-valve D, and is open direct into the cylinder, this openingbeing covered by the piston B. This piston is preferably elongated, asshown, and secured thereto is a pistonrod B', which is attached to thepump-piston of the ordinary construction. In grooves in this piston aresuitable packing-rings b b, and beyond the packing-rings at each end ofthe piston are exhaust-grooves h/ and b2, which align with passages fromthe steam-chest D as well as with the exhaust-port d2, as fullydescribed hereinafter.

In the port a, extending in the present instance into the head A of thecylinder, is a valve c, which closes the port more or less when steam isexhausted, so as to cushion the piston on its downward stroke. Thisvalve is regulated by an adj listing-screw c', by means of which more orless opening can be given to the port. The area of the passages d3beyond the valve is equal to the area of the port a, so that the steamin its admission to the cylinder is not wire-drawn, the valve c simplycontrolling the exhaust. The valve is a disk-valve having stems whichare guided in ways in the head of the cylinder.

' The slide-valve D is controlled by a piston E, made hollow in thepresent instance and having openings e to allow steam to enter the valvefrom the steam-chest D', and in each end of this piston are small holese', through which steam is wire-drawn and enters the spaces x at eachend of the steam-chest. The space communicates with a passage i, whichextends some distance below the exhaust-port a2 and enters the cylinderat c", so that when the piston B is in the position shown in Fig. l atthe end of its stroke the groove b2 will align with this opening t" andat the same time with the exhaust-port a2 and consequently exhaust thesteam from the space at one end of the valve-piston B, and steam at theopposite end of the piston will consequently force the piston and itsvalve in the direction of the arrow, shifting the slide-valve- D, andthe piston B will then move in the opposite direction. The piston willimme- .diately'cut'off the communication between the space and theexhaust-passage c2, and steam will flow into the space .fr from thesteam-chest D. When the piston travels to the opposite end of thecylinder, the groove b will align with the opening '3 of the passagez'2, which will exhaust the steam from the space x at the opposite endof the valve-pistonE, and thus reverse the slide-valve.

By the above-described mechanism it will be seen that thevalve-operating mechanism is contained within the steam-chest and is notliable to be injured or become disarranged. This valve mechanism, itwill be understood, can be used for other purposes than operatingsteam-pumps.

I claim as my inventionl. The combination in valve mechanism, of thecylinder having a steam-chest, ports a a extending from the ends of thecylinder to the steam-chest, a central exhaust-passage opening into thesteam-chest and opening into the cylinder, a piston adapted to thecylinder and having grooves which alternately communicate with theexhaust-passage, a slidevalve controlling the admission of steam to IOOand exhaust of steam from the cylinder, a similar piston controllingsaid Valve and having passages therein communicating with thesteam-chest and with spaces beyond each end of the piston, said passagesbeing of such diameter as to wire-draw the steam, and passages extendingfrom each end space to a central point in the cylinder some distancefrom the opening into the exhaust-passage so that when the piston in thecylinder reaches either of the extreme positions one of the grooves inthe piston will form a communication lbetween said passages and theexhaust-passage, substantially as described.

2. The combination of the cylinder A, pis

